MedicalResearch.com Interview with: Thomas Wisniewski MD Lulu P. and David J. Levidow Professor of Neurology Professor; Director Aging and Dementia New York University School of Medicine Dept. of Neurology, Psychiatry and Pathology New York, NY  10016 Medical Research: What is the background for this study? What are the main findings? Dr. Wisniewski: Chronic wasting disease (CWD) infects large numbers of deer and elk, with the potential to infect humans. Currently no prionosis has an effective treatment.  This is a relatively new prion disease that has many similarities to bovine spongiform encephalopathy which spread to humans to produce new variant Creutzfeldt-Jakob disease. Chronic wasting disease is the most infectious prion disease to date; having the potential to spread by aerosol. Previously, we have demonstrated we could prevent transmission of prions in a proportion of susceptible mice with a mucosal vaccine. In the current study, white-tailed deer were orally inoculated with attenuated Salmonella expressing PrP, while control deer were orally inoculated with vehicle attenuated Salmonella. Once a mucosal response was established, the vaccinated animals were boosted orally and locally by application of polymerized recombinant PrP onto the tonsils and rectal mucosa. The vaccinated and control animals were then challenged orally with CWD-infected brain homogenate. Three years post CWD oral challenge all control deer developed clinical CWD (median survival 602 days), while among the vaccinated there was a significant prolongation of the incubation period (median survival 909 days; p=0.012 by Weibull regression analysis) and one deer has remained CWD free both clinically and by RAMALT and tonsil biopsies. This negative vaccinate has the highest titers of IgA in saliva and systemic IgG against PrP. Western blots showed that immunoglobulins from this vaccinate react to PrP^CWD. We document the first partially successful vaccination for a prion disease in a species naturally at risk. (more…)